East opens a weak 2♦, and you choose to pass. West raises to 3♦, over which partner (1) bids 4♦, or (2) doubles, while East passes in either case.
Try (if you can) to ignore (2) while considering what to bid with the East hand in the first auction, (1). If partner is 6-5 in the majors, as well he might be, do you want to try 4♥ or 5♣?
Now consider (2), ignoring (1): Can you afford to cue 4♦ and correct 4M to 5♣? Or might partner take this sequence as a second cue in support of his major? Should you perhaps content yourself with 5♣?

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Last match of the regional Swiss, likely to determine the winner